Vasa Previa occurs when one or more of the baby’s placental or umbilical blood vessels cross the entrance to the birth canal beneath the baby.  When the cervix dilates or the membranes rupture, the unprotected vessels can tear, causing rapid fetal hemorrhage. When the baby drops in to the pelvis, the vessels can be compressed, compromising the baby’s blood supply and causing oxygen deprivation.

Vasa Previa occurs once in every 2,000 to 3,000 births. The fetal mortality rate is estimated to be as high as 95% if the condition is not prenatally diagnosed.

Women with the following conditions are at risk and should be investigated with transvaginal color Doppler ultrasound:

• Low-lying placenta or placenta previa
• Bilobed or succenturiate-lobed placenta
• Velamentous insertion of the cord
• In-vitro fertilization pregnancies
• Multiple pregnancies
• History of uterine surgery or D&C
• Painless bleeding

We support making color Doppler scanning of the placental-umbilical cord connection standard practice during all routine obstetrical ultrasounds.

Transvaginal ultrasound is used to view aberrant vessels crossing the cervix. Color Doppler ultrasound is used to measure the velocity of blood flow. Color Doppler ultrasound can be used to listen to the fetal heartbeat, examine the fetal heart for defects, and estimate placental blood flow. During this type of ultrasound, distinct colors show the different rates of blood flow. The colors show the location of fetal vessels thereby eliminating or confirming the diagnosis of Vasa Previa.

If bleeding occurs, the source of blood should be investigated with a blood test to determine whether it is maternal or fetal, provided the baby is not in distress. In cases of significant blood loss, and/or an abnormal fetal hear rate, emergency Cesarean section and blood transfusions have been shown to increase the survival rate for these babies.

The technology exists to detect Vasa Previa, but it is rarely diagnosed because prenatal screening for the condition is not the standard of care. Our goal is to make it a standard of care so that no more babies will die from this avoidable tragedy.

Visit the International Vasa Previa Foundation at www.vasaprevia.com